Tobacco leaf classifier

ABSTRACT

A tobacco leaf classifier including a primary separation chamber and a secondary separation chamber, said secondary chamber receiving middlings from said first chamber and each of said chambers operating in independent air circuits.

United States Patent Inventor Appl. No

Filed Patented Assignee TOBACCO LEAF CLASSIFIER 3 Claims, 2 DrawingFigs.

Int. Cl B07b 3/00 Field oiSearch 209/132- Primary ExaminerFrank W.Lutter Assistant ExaminerRa1ph .1. Hill Attorney-Murray SchafferABSTRACT: A tobacco leaf classifier including a primary separationchamber and a secondary separation chamber, said secondary chamberreceiving middlings from said first chamber and each of said chambersoperating in independent air circuits.

G I ,1 H l 52 I rights are claimed.

This invention relates to a method and apparatus forclassifying tobaccoleaf.

U.S. Pat. Nos. 2,941,667 and 3,034,646 disclose pneumatic tobacco leafclassifiers having as an object the separation of leaf or free laminafrom stem'attached-lamina or other unwanted particles in a tobaccomixture. Both patents disclose apparatus including an air supply and apair of separating chambers in and through which the tobacco mixture isblown. The dual chambers individually act upon only a portion of themixture. Actually such apparatus is an outgrowth of the prior singlechamber devices and was provided with a second chamber to obtain somebenefitfrom an excess air supply.

The apparatus of both'the aforementioned patents has enjoyedconsiderable commercial success, nevertheless they have been found tohave certain serious disadvantages and defects. In each, the airchambers are interconnected creating an interference in each chamber ofthe air supply. Effective separation, because of this interference, ishampered. A second disadvantage arises from thefact that there is onlyone air supply which prevents the selection and control of varyingairflows and forces for the particular lamina in each of the separatechambers.

Another disadvantage arises from the fact that, in each of theaforementioned patents the second separator was designed merely as anauxiliary and was quite small relative to the primary separatingchamber. The second chamber is thus not very effective in separatingleaf lamina from stems and other impurities.

It is the primary object of the present invention to provide a methodand apparatus over coming the noted disadvantages of the prior art andbeing considerably more effective and efficient.

The concept of this invention is to provide two distinct and majorseparating chambers, two air supplies one for each chamber and toprovide an air lock distributing means between the two chambers.

Other objects, features and concepts will appear as the description ofthe particular physical embodiment selected to illustrate the inventionprogresses. In the appended drawings;

FIG. 1 is a side elevational view of the novel tobacco classifyingapparatus; and

FIG. 2 is a plan view thereof.

With reference to FIG. 1, there is seen a classifier comprising astructure generally designated S on top of which is an intake unit andthe end 12 of which leads from a previous separator or from a thresheror other tobacco mixture supply. The intake unit 10 is provided with abaffle 14 and an air lock rotor 16 which deposits the incoming tobaccomixture onto a winnower 18 for dispersion in the interior or primarychamber 20 of the classifier S.

The tobacco mixture is introduced into the intake unit 10 by pneumaticmeans located in the prior separator or tobacco mixture supply forexample, augmented by suction blower22 connected by means of duct 24 tothe intake unit 10. A screen 25 is provided to prevent the tobaccomixture from entering into blower 22.

In the drawings the flow of air and the streams they follow separatingchambers 40 and 42. The tobacco mixture within primary chamber 20 isforced by the air entering through plenums 36 to separate, the lighterleaf lamina exhausting through the duct 40 while the heavier particlesfall onto the endless moving conveyor belt 44 traversing the bottomportion of the primary chamber 20.

The tobacco mixture on conveyor 44 is carried to an air lock rotor 46rotating in the direction of the arrow 48 which hurls the tobacco acrossthe width of and disperses the mixture into a secondary chamber 50formed at the base of duct 42. Meanwhile the entrant air from plenum 34flows beneath the conveyor 44 into the secondary chamber 50 causing theupward separation of the additional light leaflamina from the stem orother particles. The remaining stern and lamina mixture falls intoanother air lock 52 and'is exhausted through duct 54 into anotherclassifier or thresher unit as desired.

The light lamina from both the primary and secondary separation chambersis exhausted via ducts 40 and 42 to a combined discharge separation unit56, (similar .in construction to the intake unit 10) into or onto acollector such as a conveyor (not shown). The exhaustion of the laminais facilitated by connection, via ducts 60 and 62, of the discharge unit56 to the suction ends of blowers 26 and 28 respectively.

Following the above description it will be seen that the presentinvention provides truly dual separating chambers of substantial sizesufficient to separate in each light lamina from heavy stems; completelyseparate and independent air supplies capable of individual controlairflow; (dampening devices and air control means may be used sincetheir details are well known in the art); and an air lock between thetwo chambers which effectively disperses the tobacco from the primarychamber into the secondary chamber while keeping a seal between the twochambers so that no interaction between the air supplies occur.

In the structure shown, the blower is made to serve both the intake andthe discharge ends of the separator, the complete separation of the airstreams is accomplished by providing a divided air discharge unit 56 andseparate fans, 26 and 28. However, the two ducts 40 and 42 could carrythe lamina to completely independent discharge units, the essentialfeature being to provide separate fans and damper controls for each airsupply. If the air supplies are to be recirculated throughthe machine,the inlet chamberto the machine must provide a partition 64 or similarmeans for directing the one air supply to the primary separating chamber20 and the other air supply to the e secondary chamber 50 as shown.

It is also noted that it is possible to provide more than two separationchambers. In fact the number of separation chambers may be multiplied asdesired, although it is believed that with more than the two providedhere in increase in efficiency which might be obtained is not worth theextra cost of fabrication.

Further description of the drive means, damper controls motor means forthe conveyor etc., are not believed necessary in view of the descriptionof similar items in the aforementioned patents. The structure,operation, functioning and the advantages of the present classifier ofthe present invention and the underlying principles thereof will befully apparent from the above description. lt will be further apparentthat changes may be made in the various parts without departing from theprinciples and spirit of the invention as defined in the followingclaims.

lclaim:

l. A classifier for separating lamina product in a tobacco mixture,comprising a first and second sealed separating chamber connected by anair lock rotor, each of said chambers having air entrant openings andair exit openings disposed generally parallel to each other for airflow,means for independently flowing air in a closed circuit through each ofsaid chambers means for introducing a tobacco mixture into the first ofsaid chambers whereby said airflow causes the separation of laminaproduct from said tobacco mixture, said lamina product being carried bysaid air flow through the exit opening of said first chamber, means forcollecting the remaining tobacco mixture and for introducing saidremaining tobacco mixture into said second separation chamber throughsaid air lock, whereby the airflow therein causes the further separationof lamina product from said remaining tobacco mixture, said laminaproduct being carried by said airflow through said exit opening of saidsecond chamber, a pair of tobacco-air separators connected respectivelyto the exit openings of each chamber for separating the lamina for saidairflow, said airflow means comprising a pair of suction blowers, theblower end of each being connected respectively to the entrant openingsof said chambers, the suctions ends of each being connected respectivelyto the tobacco-air separator of each chamber, whereby airflow andseparation of tobacco within each chamber is maintained independentlythrough said closed circuit.

2. The classifier according to claim 1 wherein the means for introducingthe tobacco comprises a closed housing having a tobacco entrant opening,a tobacco exit opening and air exit opening, said tobacco entrantopening being located in the top of said housing and adjacent one sidethereof, said tobacco exit opening being located opposite to saidentrance, said air exit opening being located in the side of saidhousing opposite and in the same vertical plane as the side adjacentsaid tobacco entrant and exit openings, solid baffle means being adaptedto prevent transverse movement of said tobacco within said housing, airlock rotor means located at said tobacco exit opening, suction meanslocated at said air exit to draw air from said housing whereby tobaccois caused to enter said entrant opening and to flow vertically from saidentrant opening past said baffle and to exit by said air lock rotormeans while said air exits oppositely therefrom.

3. The classifier according to claim 1 in which the tobaccoair separatorcomprises a closed housing having a tobacco and air entrant opening, atobacco exit opening and a separate air exit opening, a tobacco and airentrant opening being located in the top of said housing and adjacentone side thereof, said tobacco exit opening being located opposite tosaid entrance, said airexit opening being located in the side of saidhousing opposite and in the same vertical plane as the side adjacentsaid tobacco entrant and exit openings, solid baffle means locatedcentrally within said housing, and in a vertical plane generallyperpendicular to the plane of said openings, said baffle means beingadapted to prevent transverse movement of said tobacco within saidhousing, the suction end of the suction-blower means located at said airexit to draw air from said housing whereby tobacco is caused to entersaid entrant opening past said baffle and to exit by said tobacco exitopening while air exits only through said air exit opening.

1. A classifier for separating lamina product in a tobacco mixture,comprising a first and second sealed separating chamber connected by anair lock rotor, each of said chambers having air entrant openings andair exit openings disposed generally parallel to each other for airflow,means for independently flowing air in a closed circuit through each ofsaid chambers means for introducing a tobacco mixture into the first ofsaid chambers whereby said airflow causes the separation of laminaproduct from said tobacco mixture, said lamina product being carried bysaid air flow through the exit opening of said first chamber, means forcollecting the remaining tobacco mixture and for introducing saidremaining tobacco mixture into said second separation chamber throughsaid air lock, whereby the airflow therein causes the further separationof lamina product from said remaining tobacco mixture, said laminaproduct being carried by said airflow through said exit opening of saidsecond chamber, a pair of tobacco-air separators connected respectivelyto the exit openings of each chamber for separating the lamina for saidairflow, said airflow means comprising a pair of suction blowers, theblower end of each being connected respectively to the entrant openingsof said chambers, the suctions ends of each being connected respectivelyto the tobacco-air separator of each chamber, whereby airflow andseparation of tobacco within each chamber is maintained independentlythrough said closed circuit.
 2. The classifier according to claim 1wherein the means for introducing the tobacco comprises a closed housinghaving a tobacco entrant opening, a tobacco exit opening and air exitopening, said tobacco entrant opening being located in the top of saidhousing and adjacent one side thereof, said tobacco exit opening beinglocated opposite to said entrance, said air exit opening being locatedin the side of said housing opposite and in the same vertical plane asthe side adjacent said tobacco entrant and exit openings, solid bafflemeans being adapted to prevent transverse movement of said tobaccowithin said housing, air lock rotor means located at said tobacco exitopening, suction means located at said air exit to draw air from saidhousing whereby tobacco is caused to enter said entrant opening and toflow vertically from said entrant opening past said baffle and to exitby said air lock rotor means while said air exits oppositely therefrom.3. The classifier according to claim 1 in which the tobacco-airseparator comprises a closed housing having a tobacco and air entrantopening, a tobacco exit opening and a separate air exit opening, atobacco and air entrant opening being located in the top of said housingand adjacent one side thereof, said tobacco exit opening being locatedopposite to said entrance, said air exit opening being located in theside of said housing opposite and in the same vertical plane as the sideadjacent said tobacco entrant and exit openings, solid baffle meanslocated centrally within said housing, and in a vertical plane generallyperpendicular to the plane of said openings, said baffle means beingadapted to prevent transverse movement of said tobacco within saidhousing, the suction end of the suction-blower means located at said airexit to draw air from said housing whereby tobacco is caused to entersaid entrant opening past said baffle and to exit by said tobacco exitopening while air exits only through said air exit opening.